发布求助
文献互助 智能选刊 最新文献

2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications最新文献

筛选
英文 中文
Pilot-symbol-assisted communications with noncausal and causal Wiener filters 具有非因果和因果维纳滤波器的导视符号辅助通信
2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications Pub Date : 2008-07-06 DOI: 10.1109/SPAWC.2008.4641616
Sami Akın, M. C. Gursoy
{"title":"Pilot-symbol-assisted communications with noncausal and causal Wiener filters","authors":"Sami Akın, M. C. Gursoy","doi":"10.1109/SPAWC.2008.4641616","DOIUrl":"https://doi.org/10.1109/SPAWC.2008.4641616","url":null,"abstract":"In this paper, pilot-assisted transmission over time-selective flat fading channels is studied. It is assumed that noncausal and causal Wiener filters are employed at the receiver to perform channel estimation with the aid of training symbols sent periodically by the transmitter. For both filters, the variances of estimate errors are obtained from the Doppler power spectrum of the channel. Subsequently, achievable rate expressions are provided. The training period, and data and training power allocations are jointly optimized by maximizing the achievable rate expressions. Numerical results are obtained by modeling the fading as a Gauss-Markov process. The achievable rates of causal and noncausal filtering approaches are compared. For the particular ranges of parameters considered in the paper, the performance loss incurred by using a causal filter as opposed to a noncausal filter is shown to be small. The impact of aliasing that occurs in the undersampled version of the channel Doppler spectrum due to fast fading is analyzed. Finally, energy-per-bit requirements are investigated in the presence of noncausal and causal Wiener filters.","PeriodicalId":197154,"journal":{"name":"2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122118522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 4
On the constrained stochastic gradient algorithm behavior in wireless communication networks 约束随机梯度算法在无线通信网络中的行为研究
2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications Pub Date : 2008-07-06 DOI: 10.1109/SPAWC.2008.4641603
J. Kolodziej, O. J. Tobias, R. Seara, D. Morgan
{"title":"On the constrained stochastic gradient algorithm behavior in wireless communication networks","authors":"J. Kolodziej, O. J. Tobias, R. Seara, D. Morgan","doi":"10.1109/SPAWC.2008.4641603","DOIUrl":"https://doi.org/10.1109/SPAWC.2008.4641603","url":null,"abstract":"The purpose of this paper is to report on an unsuitable behavior of the constrained stochastic gradient (CSG) algorithm for adaptive beamforming in the combination of two events: one or more interference angles-of-arrival are close to the signal angle-of-arrival and the angle spreads of the involved signals are small. In this situation, the CSG algorithm stresses the co-channel interference minimization more than the maximization of the power radiated to the in-cell mobile terminal. We term this phenomenon unbalanced behavior and provide an analytical study to explain it.","PeriodicalId":197154,"journal":{"name":"2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications","volume":"661 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120877900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Blind SIMO channel identification using a sparsity criterion 使用稀疏性准则的盲SIMO信道识别
2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications Pub Date : 2008-07-06 DOI: 10.1109/SPAWC.2008.4641612
A. Aíssa-El-Bey, K. Abed-Meraim
{"title":"Blind SIMO channel identification using a sparsity criterion","authors":"A. Aíssa-El-Bey, K. Abed-Meraim","doi":"10.1109/SPAWC.2008.4641612","DOIUrl":"https://doi.org/10.1109/SPAWC.2008.4641612","url":null,"abstract":"In this paper, we are interested in blind identification of single-input multiple-output (SIMO) systems. Using the sparsity property of impulse response, we propose an iterative method which minimizes a cost function based on the lscrp norm. This norm is considered as a good sparsity measure. The simulations show that the proposed method outperforms existing techniques in terms of estimation error and robustness to channel order overestimation.","PeriodicalId":197154,"journal":{"name":"2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122434800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 30
Multi-access channels with multiple decode-and-forward relays: Rate region and asymptotic sum-rate 具有多个译码转发中继的多址信道:速率区域和渐近和速率
2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications Pub Date : 2008-07-06 DOI: 10.1109/SPAWC.2008.4641630
A. del Coso, C. Ibars
{"title":"Multi-access channels with multiple decode-and-forward relays: Rate region and asymptotic sum-rate","authors":"A. del Coso, C. Ibars","doi":"10.1109/SPAWC.2008.4641630","DOIUrl":"https://doi.org/10.1109/SPAWC.2008.4641630","url":null,"abstract":"This paper considers the Gaussian multiple access channel (MAC) assisted by N parallel relays. For the channel, the rate region with decode-and-forward is derived, considering both full-duplex and half-duplex relaying. The asymptotic sum-rate of the channel, under Rayleigh-distributed fading, is also presented. We prove that the sum-rate of the MAC with D&F relays converges almost surely to the sum-rate without relays. Hence, at the asymptote, multiuser diversity makes D&F relaying useless. Nevertheless, is also shown here that for finite number of users, the sum-rate converges to a strictly increasing function of the number of relays.","PeriodicalId":197154,"journal":{"name":"2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129283361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Robust pilot-aided channel estimator for time-varying OFDM channels 时变OFDM信道的鲁棒导频辅助信道估计
2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications Pub Date : 2008-07-06 DOI: 10.1109/SPAWC.2008.4641659
R. Vigelis, C. Cavalcante
{"title":"Robust pilot-aided channel estimator for time-varying OFDM channels","authors":"R. Vigelis, C. Cavalcante","doi":"10.1109/SPAWC.2008.4641659","DOIUrl":"https://doi.org/10.1109/SPAWC.2008.4641659","url":null,"abstract":"This paper deals with time-varying channel estimation in orthogonal frequency division multiplexing (OFDM) systems by means of pilot-aided strategies. A robust estimator which does not depend on the channel statistics is proposed. The derivation is based on a constrained filtering approach and particular cases are analyzed. Simulation results are provided in order to verify the better performance of the proposal when compared to estimators reported in the literature.","PeriodicalId":197154,"journal":{"name":"2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127573569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Blind estimation of nonlinear instantaneous channels in multiuser CDMA systems with PSK inputs PSK多用户CDMA系统中非线性瞬时信道的盲估计
2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications Pub Date : 2008-07-06 DOI: 10.1109/SPAWC.2008.4641602
C. Fernandes, G. Favier, J. Mota
{"title":"Blind estimation of nonlinear instantaneous channels in multiuser CDMA systems with PSK inputs","authors":"C. Fernandes, G. Favier, J. Mota","doi":"10.1109/SPAWC.2008.4641602","DOIUrl":"https://doi.org/10.1109/SPAWC.2008.4641602","url":null,"abstract":"A new method for estimating nonlinear instantaneous channels in a multiuser Code Division Multiple Access (CDMA) environment is presented in this paper. This kind of nonlinear models has important applications in the field of telecommunications, e.g. to model uplink channels in Radio Over Fiber multiuser communication systems. The proposed technique is based on the decomposition of a tensor composed of covariances of the chip-rate sampled received signals, the transmitted signals being assumed to be Phase Shift Keying (PSK) modulated. The considered tensor-based approach allows a great flexibility on the number of antennas and the spreading factor, which is particularly desirable when identifying nonlinear systems. Two blind channel estimation algorithms are considered: the Alternating Least Squares (ALS) algorithm and a non-iterative algorithm based on Eigenvalue Decompositions (EVD). The performance of the proposed estimation algorithms is illustrated by means of computer simulations.","PeriodicalId":197154,"journal":{"name":"2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114379696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 6
Dynamic bit allocation and differential quantization in feedback link for robust power allocation in multiuser opportunistic beamforming 多用户机会波束形成中反馈链路的动态位分配和差分量化
2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications Pub Date : 2008-07-06 DOI: 10.1109/SPAWC.2008.4641619
N. Zorba, A. Pascual-Iserte, A. Neira
{"title":"Dynamic bit allocation and differential quantization in feedback link for robust power allocation in multiuser opportunistic beamforming","authors":"N. Zorba, A. Pascual-Iserte, A. Neira","doi":"10.1109/SPAWC.2008.4641619","DOIUrl":"https://doi.org/10.1109/SPAWC.2008.4641619","url":null,"abstract":"Multi-antenna systems provide advantages in terms of link quality and multiuser access capabilities, which can be achieved by using schemes as multibeam opportunistic beamforming. This scheme only requires partial channel state information at the transmitter (CSIT) in terms of the equivalent channel moduli. This paper deals with the problem of feeding back the CSI from the multiple receivers to the base station (BS) transmitter through limited capacity feedback links. This involves a quantization and a delay that produces errors in the CSIT. In this sense, the proposed scheme in this paper is based on a robust design that takes into account these errors. Additionally, a dynamic bit allocation in the feedback among the users is derived, and combined with differential quantization to minimize the transmit power. It considers both the userspsila sensitivities to the quantization errors and the Doppler frequencies due to the mobility. Simulation results show the benefits from using such schemes.","PeriodicalId":197154,"journal":{"name":"2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications","volume":"107 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126355204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Coding strategies for CDMA packet data networks with reduced rank multiuser detection, ARQ and Packet Combining 基于降阶多用户检测、ARQ和分组合并的CDMA分组数据网络编码策略
2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications Pub Date : 2008-07-06 DOI: 10.1109/SPAWC.2008.4641572
B. Mouhouche, Cédric Artigue
{"title":"Coding strategies for CDMA packet data networks with reduced rank multiuser detection, ARQ and Packet Combining","authors":"B. Mouhouche, Cédric Artigue","doi":"10.1109/SPAWC.2008.4641572","DOIUrl":"https://doi.org/10.1109/SPAWC.2008.4641572","url":null,"abstract":"Reduced-rank code division multiple access (CDMA) multi-user detection has received a lot of attention recently. The output SINR provided by a reduced-rank receiver depends on the filter rank and is confined between the SINRs of the single user matched filter (SUMF) and the minimum mean squared error (MMSE) receiver. In packet CDMA data networks like HSDPA, the measure of performance is the throughput. Thus, previous results on reduced-rank MMSE receivers SINR cannot be used directly. In this paper, we study the throughput of CDMA data networks using reduced-rank MMSE receivers, automatic retransmission request (ARQ) and packet combining. We derive the expression of the system throughput as the function of the filter rank, the coding rate and the number of retransmissions. We present simulation results to highlight the behavior of the maximum throughput as a function of the filter rank and the coding rate. We then conclude on coding strategies to adopt depending on the signal to noise ratio and the receiver rank in order to maximize the system throughput.","PeriodicalId":197154,"journal":{"name":"2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications","volume":"28 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114047763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Iterative decoding bounds for multiuser multilevel FSK 多用户多电平FSK的迭代译码界
2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications Pub Date : 2008-07-06 DOI: 10.1109/SPAWC.2008.4641583
M. Sharma, J. Portugheis
{"title":"Iterative decoding bounds for multiuser multilevel FSK","authors":"M. Sharma, J. Portugheis","doi":"10.1109/SPAWC.2008.4641583","DOIUrl":"https://doi.org/10.1109/SPAWC.2008.4641583","url":null,"abstract":"In this work we study joint multiuser detection using factor graphs for an N frequency T user noisy multiple access channel. This channel may model a frequency hopped code division multiple access system. The system is separated in two parts: multiuser detector and a code. We present a factor graph for the multiuser detector and obtain from it extrinsic information transfer (EXIT) curves. Paired with the EXIT curves of low density parity check and repeat accumulate codes, we obtain values for the signal to noise ratio (SNR) that bound the systempsilas performance. The EXIT curves for the codes are presented from the detectors perspective. The results show that rates close to the sum capacity are achievable.","PeriodicalId":197154,"journal":{"name":"2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123862723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
Optimal training for frequency offset estimation in correlated-rice frequency-selective channel 相关米选频信道中频偏估计的最优训练
2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications Pub Date : 2008-07-06 DOI: 10.1109/SPAWC.2008.4641559
P. Ciblat, P. Bianchi, M. Ghogho
{"title":"Optimal training for frequency offset estimation in correlated-rice frequency-selective channel","authors":"P. Ciblat, P. Bianchi, M. Ghogho","doi":"10.1109/SPAWC.2008.4641559","DOIUrl":"https://doi.org/10.1109/SPAWC.2008.4641559","url":null,"abstract":"We consider carrier frequency offset (CFO) estimation for single-carrier and single-user transmission over a frequency-selective channel. When training is solely devoted to frequency synchronization, it is important to design the training to optimize CFO estimation performance. In this paper we exhibit the training sequence that minimizes the Cramer-Rao bound associated with the carrier frequency offset and averaged over the channel statistics following a correlated Ricean fading channel model. Simulations show significant improvements compared to the standard pseudo-random white training sequence.","PeriodicalId":197154,"journal":{"name":"2008 IEEE 9th Workshop on Signal Processing Advances in Wireless Communications","volume":"318 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115833017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 5
首页 上一页 下一页 尾页
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整，为了账户安全，请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们：info@booksci.cn Book学术提供免费学术资源搜索服务，方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号：604180095
Book学术官方微信